Cleaning wiping products (or wipes or sheets) in various forms have long been used to clean debris from surfaces in residential and commercial environments. Most available cleaning wipe products have the same basic form, including a relatively thin base comprised of a fibrous material (or web) that is at least somewhat supple to enhance user handling. To this end, a number of different materials and manufacturing techniques have been developed (e.g., woven, nonwoven, or knitted base structure comprised of natural and/or synthetic fibers), each having certain characteristics adapted to at least partially satisfy a particular end use. In addition, efforts have been made to incorporate certain additives into the fiber web to better address the needs of specific applications.
For example, residential or household consumers commonly use cleaning wipes or cloths to remove debris from various surfaces around the home. A so-called “dust cloth” is an exemplary item used for these applications. While these and similar cloth materials are quite useful for removing dust and other minute particles from surfaces, they cannot readily remove larger and/or heavier debris (e.g., sand, food crumbs, etc.) because these particles will not adhere to, or be retained by, the cloth. Though not necessarily developed to address this problem, common cloth treatment materials, such as wax or oil, may enhance the ability of the cloth to retain some larger debris particles due to an inherent “wetness” of the additive. Treated dust cloths leave a residue on the contacted surface that, while desirable for certain uses (e.g., furniture polishing), is unwanted for most household cleaning activities (e.g., cleaning a counter or floor surface). Further, when used for general cleaning purposes, treated cloths quickly become saturated with particles at their outer surface, thereby limiting use to short cleaning operations and requiring frequent cleaning of the wipe itself (i.e., removing accumulated particles).
Other wipe products marketed for household cleaning are adapted to include an electrostatic characteristic that, in theory, attracts debris particles to the otherwise “dry” wipe. Again, however, these dry wipes are often unable to consistently retain relatively large and/or heavy particles over extended periods of use. That is to say, relatively large and/or relatively heavy particles do not readily adhere to the dry, electrostatic-type wipes and other dry wipes. Further, the surface of these products quickly becomes “clogged” with particles, such that the collected debris must be repeatedly removed from the wipe's surface.
Of course, removing debris from surfaces is not limited to household cleaning applications. Many industrial applications entail the use of a cleaning wipe. For example, the vehicle painting/repainting industry and wood finishing industry commonly make use of “tack cloths” to remove debris from surfaces that are to be painted or stained. Generally, tack wipes or tack cloths comprise some form of textile material that has an open structure and is treated with a pressure sensitive adhesive or some other tacky polymer to give the tack cloth a sticky or tacky characteristic. When such a wipe is rubbed over a surface, foreign matter which is present on the surface will adhere to the wipe and be removed. While useful for these industrial applications, available tack wipes purposefully contain relatively high levels of the tacky material to ensure complete removal of dust and other fine particles. Known tack wipe manufacturing techniques purposefully coat the tacky material at the outer surfaces of the wipe. This coating, in turn, imparts an adhesive or sticky “feel” to the wipe, and creates significant drag as the tack wipe is moved along the surface being cleaned. Although such tack wipes have been used in the automotive painting/repainting and wood finishing industries, the negative attributes of available tack wipes have hindered their viability for certain commercial or residential uses (e.g., household or general industrial cleaning).
By way of reference, typical pressure sensitive adhesives (PSA) used to impart the tacky characteristic to a tack cloth are 100% solids hot melt PSA, radiation curable PSA, PSA dissolved in organic solvent, and latex-based PSA. Regardless, once the base web construction of the tack cloth has been formed, the PSA (or other tacky additive) is then applied. Known techniques include spraying, dip coating, roll coating, etc. In more general terms, the PSA (or other tacky material) is applied to the outer surfaces of the web; in most instances, an entire thickness of the web material is saturated with the PSA. In any event, the outer surfaces of the resultant tack cloth contain the highest concentration of the PSA, leading to the problems of drag described above.
Some efforts have been made to alter the above-described tack cloth construction to provide a cleaning wipe having a tacky characteristic with lessened adhesive “feel” and surface drag. Such efforts have generally focused on the careful selection of the type and amount of the additive material, and/or the pattern of application of the adhesive as a means for reducing drag so as to improve particle pick-up while maintaining the ability of the cleaning sheet to glide across the surface being cleaned. For example, in some approaches, relatively small levels (no more than 10 g/m2, more preferably no greater than 2 g/m2) of a polymeric additive, usually a pressure sensitive adhesive, is applied at discrete zones along the cleaning wipe surface. In such constructions, if the polymeric additive level is too high, the cleaning sheet will not glide easily across the surface being cleaned and/or may tend to leave residue on the surface. Though the polymeric additives and patterns used in such wipes are different from typical tack cloth configurations, the conventional technique of applying the polymeric additive to the outer surfaces of the base web is still followed. As a result, even though the reduction in adhesive level and zoned distribution may improve handling, the same issues described above will likely remain and others may be raised. That is to say, the zones at which the polymeric additive is applied may still “feel” sticky, and may create an unacceptable level of drag when the cleaning wipe is moved along a surface. Further, by reducing the level and location (i.e., provided along less than an entirety of the cleaning wipe outer surface) of the polymeric additive, the resultant cleaning wipe may be less capable of retaining sufficient amounts of particles. Also, because the polymeric additive is applied to the surface of the base web, even where the web has a relatively open construction, the cleaning wipe surface will again become clogged with particles relatively quickly.
Cleaning wipes continue to be highly popular. The ability to collect large amounts of relatively sizable and/or heavy particles has not yet been fully satisfied with a product acceptable to most users. Therefore, a need exists for a cleaning wipe having tacky attribute with minimal tackiness along the working surface thereof, along with a method of manufacturing such a cleaning wipe.